Method for manufacturing a wheel for vehicles

ABSTRACT

A wheel for vehicles may include a rim coupled to a tire, and a spoke-shaped disc including a spoke and a vent hole, the spoke-shaped disc being coupled to a side surface of the rim to support the rim, in which a coupling zone between the spoke of the spoke-shaped disc and the rim and a coupling zone between a portion of the spoke-shaped disc formed with the vent hole and the rim have a height difference in a wheel axis direction, to allow the spoke-shaped disc to support the rim at an interior and an exterior of the rim.

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a Divisional of U.S. patent application Ser.No. 14/954,764, filed Nov. 30, 2015, which claims priority to KoreanPatent Application No. 10-2015-0053541 filed Apr. 16, 2015, the entirecontents of which are incorporated herein for all purposes by thesereferences.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a wheel for vehicles and a method formanufacturing the same. More particularly, it relates to a wheel forvehicles which is capable of achieving superior design to a generalsteel wheel owing to design freedom obtained by a spoke-shaped disc, ofachieving an increased natural frequency and rigidity while having thesame level of a disc thickness and weight as the general steel wheel,and of achieving road noise reduction performance, and a method formanufacturing the same.

Description of Related Art

Recently, increased vehicle fuel efficiency and reduced noise duringtraveling have been demanded by vehicle users. In particular, advancedusers prefer vehicles providing a more comfortable and low noise cabin.

Road noise of a real vehicle may be broadly divided into resonancenoise, booming noise, and rumble noise. Thereamong, resonance noise isintroduced to a vehicle cabin as vibration applied from a road surfaceduring traveling is transmitted to, for example, tires, wheels, chassiscomponents, and a vehicle body.

Various specifications of wheels for vehicles have been developed toimprove road noise.

Generally, wheels for vehicles may be divided into steel wheels formedof steel and aluminum wheels formed of an aluminum alloy.

FIG. 1A is a view illustrating a conventional general steel wheel forvehicles, and FIG. 1B is a view illustrating a conventional aluminumwheel.

The steel wheel is manufactured by bonding a steel rim 1 and a disc 2 toeach other via welding and has advantages of low price and easymanufacture. However, the steel wheel is inferior in design and heavieras compared to an aluminum wheel due to characteristics of steel and aprocessing method including welding.

The aluminum wheel is manufactured using an aluminum alloy withoutwelding such that a rim 1 and spokes 3 are integrally formed. Thealuminum wheel has advantages including superior design andmarketability and light weight, but also has disadvantages including lowproductivity and high price due to characteristics of an aluminum alloyand a complicated processing method.

In recent years, to improve design of a conventional general steelwheel, a styled steel wheel having a spoke-shaped disc similar to analuminum wheel has been developed. This styled steel wheel increasesmarketability of a vehicle through improvement in wheel design.

Prior art discloses a wheel for vehicles in which a rim is formed ofsteel and a disc is formed of an aluminum alloy for improvement ofdesign, and a styled steel wheel which is manufactured by welding aspoke-shaped disc having spokes and decorative holes (or vent holes) toa rim.

In addition, prior art discloses an aluminum wheel for vehicles whichincludes a rim consisting of a cylindrical base rim configured to facethe tread of a tire and a support rim integrally protruding from anouter surface of the base rim in the circumferential direction of thebase rim, the support rim and the base rim having a hollow regioninterposed therebetween.

The aluminum wheel having the hollow region is capable of absorbing andreducing resonance noise generated from the tire via the hollow regionof the rim even if a separate sound absorption material is not used,thereby advantageously reducing noise to be transmitted to a vehiclecabin.

Meanwhile, FIG. 2 illustrates vibration in a steel wheel rim mode. Ageneral steel wheel is known as generating greater road noise by about 2dB to 3 dB as compared to an aluminum wheel. This is because the naturalfrequency of the steel wheel rim mode is within a range of 170 Hz to 200Hz that is greatly lower than that (within a range of 300 Hz or more) ofan aluminum wheel.

The aforementioned styled steel wheel may increase the natural frequencyowing to design freedom as to the structure and shape of a discsupporting a rim, which may cause performance improvement in terms ofdesign and road noise.

However, the styled steel wheel needs to increase a disc thickness inorder to achieve a high natural frequency and such a thicker disc thanthat of a conventional wheel causes an excessive wheel weight.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and should not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art already known to aperson skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing awheel for vehicles which is capable of achieving superior design to ageneral steel wheel owing to design freedom obtained by a spoke-shapeddisc, of achieving an increased natural frequency and rigidity whilehaving the same level of a disc thickness and weight as the generalsteel wheel, and of achieving road noise reduction performance, and amethod for manufacturing the same.

According to various aspects of the present invention, a wheel forvehicles may include a rim coupled to a tire, and a spoke-shaped discincluding a spoke and a vent hole, the spoke-shaped disc being coupledto a side surface of the rim to support the rim, in which a couplingzone between the spoke of the spoke-shaped disc and the rim and acoupling zone between a portion of the spoke-shaped disc formed with thevent hole and the rim may have a height difference in a wheel axisdirection, to allow the spoke-shaped disc to support the rim at aninterior and an exterior of the rim.

An end of the spoke of a peripheral portion of the spoke-shaped disc maybe coupled to an exterior position of the rim, and a vent hole positionend, corresponding to an end of the portion formed with the vent hole,of the peripheral portion of the spoke-shaped disc may be coupled to aninterior position of the rim.

An end of the spoke and the portion formed with the vent hole may becoupled, via welding, to positions of the rim having a height differencein the wheel axis direction.

According to various aspects of the present invention, a method formanufacturing a wheel for vehicles may include forming a rim configuredto be coupled to a tire and a spoke-shaped disc including a spoke and avent hole, and coupling the spoke-shaped disc to a side surface of therim such that a coupling zone between the spoke of the spoke-shaped discand the rim and a coupling zone between a portion of the spoke-shapeddisc formed with the vent hole and the rim have a height difference in awheel axis direction, to allow the spoke-shaped disc to support the rimat an interior and an exterior of the rim.

After the rim is formed of steel and the spoke-shaped disc is formed bypressing a steel panel, the rim and the spoke-shaped disc may be coupledto each other to complete a styled steel wheel.

It is understood that the term “vehicle” or “vehicular” or other similarterms as used herein is inclusive of motor vehicles in general such aspassenger automobiles including sports utility vehicles (SUV), buses,trucks, various commercial vehicles, watercraft including a variety ofboats and ships, aircraft, and the like, and includes hybrid vehicles,electric vehicles, plug-in hybrid electric vehicles, hydrogen-poweredvehicles and other alternative fuel vehicles (e.g., fuel derived fromresources other than petroleum). As referred to herein, a hybrid vehicleis a vehicle that has two or more sources of power, for example, bothgasoline-powered and electric-powered vehicles.

The methods and apparatuses of the present invention have other featuresand advantages which will be apparent from or are set forth in moredetail in the accompanying drawings, which are incorporated herein, andthe following Detailed Description, which together serve to explaincertain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A and FIG. 1B is a view illustrating a conventional wheel forvehicles according to the related art.

FIG. 2 is a view illustrating vibration in a steel wheel rim modeaccording to the related art.

FIG. 3 is a front view illustrating an exemplary wheel for vehiclesaccording to the present invention.

FIG. 4 is an exploded perspective view illustrating a configuration ofthe exemplary wheel for vehicles according to the present invention.

FIG. 5 is a sectional view taken along line “A-A” of FIG. 3.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particular intendedapplication and use environment.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that the present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

FIG. 3 is a front view illustrating a wheel for vehicles according tovarious embodiments of the present invention, and FIG. 4 is an explodedperspective view illustrating a configuration of the wheel for vehiclesaccording to various embodiments of the present invention in a separatedstate of a rim and a spoke-shaped disc before bonding.

FIG. 5 is a sectional view taken along line “A-A” of FIG. 3.

The wheel for vehicles according to various embodiments of the presentinvention is a styled steel wheel formed of steel. The wheel forvehicles includes a rim 10 configured to be coupled to a tire and aspoke-shaped disc 20 bonded to the side surface of the rim 10 viawelding to support the rim 10, the spoke-shaped disc 20 being formed bypressing a single panel.

The spoke-shaped disc 20 is formed with spokes 21 and vent holes (ordecorative holes) 22. In the disc 20, ends 21 a of the spokes 21 andends 22 of positions formed with the vent holes 22 become weld zonesbetween the disc 20 and the rim 10.

That is, weld zones between the spoke-shaped disc 20 and the rim 10include the ends 21 a of the spokes 21 and the ends 22 a of portionsformed with the vent holes 22. In the following description, the ends 22a, which are peripheral portions of the disc 20 formed with the ventholes 22, are referred to as vent hole position ends.

In addition, the wheel for vehicles according to the present inventionhas a feature of bonding and weld zones between the rim 10 and thespoke-shaped disc 20. More specifically, as illustrated in FIG. 5, amain feature of the present invention is that the end 21 a of each spoke21 and each vent hole position end 22 a, which are weld zones betweenthe disc 20 and the rim 10, have a height difference in the axialdirection about a wheel axis (hereinafter referred to as a “wheel axisdirection”).

Accordingly, positions of the rim 10 to which the disc 20 is welded,i.e. a position to which the end 21 a of each spoke 21 is welded and aposition to which each vent hole position end 22 a is welded also have aheight difference in the wheel axis direction. Weld zones between therim 10 and the disc 20 are divided into an interior weld zone and anexterior weld zone when viewed from the front side of the rim 10.

In various embodiments, the end 21 a of each spoke 21 may be welded toan exterior position of the rim 10 (the right position of FIG. 5) andeach vent hole position end 22 a may be welded to an interior positionof the rim 10 (the left position of FIG. 5). In other words, a positionof the rim 10 where the end 21 a of each spoke 21 is welded is anexterior position and a position of the rim 10 where each vent holeposition end 22 a is welded is an interior position.

As the weld zones between the rim 10 and the disc 20, i.e. the spokes 21a and the portions formed with the vent holes 22 have a heightdifference in the wheel axis direction, the disc 20 is capable ofsupporting the rim 10 in a wide range at the interior and the exteriorof the rim 10.

That is, in the styled steel wheel manufactured by bonding the rim 10and the spoke-shaped disc 20 to each other via welding, as the weld zonebetween the end 21 a of each spoke 21 and the rim 10 and the weld zonebetween each vent hole position end 22 a and the rim 10 have a heightdifference in the wheel axis direction, the disc 20 is capable ofsupporting the rim 10 in a wide range at the interior and the exteriorof the rim 10, which increases the natural frequency and rigidity of thewheel.

In a conventional styled steel wheel, a spoke-shaped disc is formed witha ring-shaped peripheral portion to be welded to the rim. At this time,the peripheral portion as a weld zone (weld line) between the rim andthe disc has a circular shape following the circumferential direction ofthe wheel.

Differently from the conventional styled steel wheel as described abovewhich has a 2-dimensional circular weld line between the rim and thedisc, in the wheel of the present invention, the weld zones between therim 10 and the disc 20 are not interconnected via a single line and, atthis time, the weld zones have 3-dimensional arrangement in which thespokes 21 and the portions formed with the vent holes 22 have a heightdifference in the wheel axis direction along the periphery of the disc20.

In conclusion, as the disc 20 supports the interior and the exterior ofthe rim 10, the natural frequency and the effective rim rigidity of thewheel may be considerably increased as compared to the conventionalgeneral steel wheel (see FIG. 1A).

The present invention analyzed factors that contribute to the naturalfrequency of the wheel for vehicles in a low frequency primary mode,i.e. in a rim mode using a phase optimization design technique andconfirmed that a height difference between a rim-spoke bonding zone anda rim-vent hole position end bonding zone is a major factor thatcontributes to the natural frequency of the wheel in the rim mode.

In particular, it was confirmed that, as the disc 20 supports the rim 10in a wider range at the interior and the exterior of the rim 10, this isadvantageous in terms of rigidity and enables an increase in naturalfrequency.

In addition, when comparing the conventional general steel wheel withthe styled steel wheel of the present invention under the condition ofthe same weight (of 9.1 kg), it could be appreciated that theconventional general steel wheel (see FIG. 1A) has a rim mode naturalfrequency of 157 Hz, whereas the styled steel wheel of the presentinvention (see FIG. 3) is increased in natural frequency to 254 Hz as aresult of setting a height difference in the wheel axis directionbetween the weld zones of the disc 20 and the rim 10, i.e. between theend 21 a of each disc spoke 21 and the vent hole position end 22 a.

In addition, the effective rim rigidity is 2,358 kgf/mm, which is about2.6 times of that of the conventional general steel wheel.

As described above, the styled steel wheel of the present invention isincreased in natural frequency than the conventional general steel wheelunder the condition of the same weight, thereby advantageously achievingimproved road noise reduction performance and increased rigidity ascompared to the conventional general steel wheel.

Of course, the styled steel wheel of the present invention including thespoke-shaped disc 20 is capable of achieving design freedom to enablevarious designs of the spokes 21, thus advantageously achieving superiordesign to the general steel wheel.

In addition, although a conventional styled steel wheel, acquired bychanging a disc shape of the general steel wheel to a spoke shape, mayachieve an increased natural frequency and rigidity as compared to thegeneral steel wheel, the conventional styled steel wheel requires arelative great disc thickness, thus suffering from an excessive wheelweight.

On the other hand, in the improved styled steel wheel of the presentinvention, the spoke-shaped disc 20 is manufactured by forming a singlepanel via pressing. In particular, to allow the disc 20 to support therim 10 in a wide range at the interior and the exterior of the rim 10,the disc 20 is manufactured such the weld zones between the disc 20 andthe rim 10, i.e. the weld zone between each spoke 21 and the rim 10 andthe weld zone between each vent hole position end 22 a and the rim 10have a height difference in the wheel axis direction and the rim 10, andthe disc 20 are welded to each other to indicate the height differenceupon bonding. In this way, it is possible to increase a required naturalfrequency and rigidity without an increase in disc thickness.

As is apparent from the above description, with a wheel for vehicles anda method for manufacturing the same, the present invention has effectsof achieving superior design to a general steel wheel owing to designfreedom obtained by a spoke-shaped disc, of achieving an increasednatural frequency and rigidity while having the same level of a discthickness and weight as the general steel wheel, and of achieving noisereduction performance owing to a height difference in the wheel axisdirection between weld zones of a disc and a rim, i.e. between a spokeand a vent hole position end.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. A method for manufacturing a wheel for vehicles,the method comprising: forming a steel rim configured to be coupled to atire; forming a spoke-shaped disc including a spoke and a vent hole bypressing a single steel panel; and coupling the spoke-shaped disc to aside surface of the rim such that a first coupling zone between thespoke of the spoke-shaped disc and the rim and a second coupling zonebetween a portion of the spoke-shaped disc formed with the vent hole andthe rim have a height difference in a wheel axis direction, to allow thespoke-shaped disc to support the rim at an interior and an exterior ofthe rim, wherein the first coupling zone between the spoke of thespoke-shaped disc and the rim and the second coupling zone between theportion of the spoke-shaped disc formed with the vent hole and the rimhave a height difference in a radial direction of the spoke-shaped disc.2. The method of claim 1, wherein an end of the spoke of a peripheralportion of the spoke-shaped disc is coupled to an exterior position ofthe rim, and a vent hole position end, corresponding to an end of theportion formed with the vent hole, of the peripheral portion of thespoke-shaped disc is coupled to an interior position of the rim.
 3. Themethod of claim 2, wherein the end of the spoke and the portion formedwith the vent hole are coupled, via welding, to positions of the rimhaving a height difference in the wheel axis direction.
 4. The method ofclaim 1, wherein an end of the spoke and the portion formed with thevent hole are coupled, via welding, to positions of the rim having aheight difference in the wheel axis direction.
 5. The method of claim 1,wherein, the coupling results in a complete styled steel wheel.